Simplify the following expression: $n = \dfrac{7}{4x} + \dfrac{1}{2x}$
In order to add expressions, they must have a common denominator. The smallest common denominator is the least common multiple of $4x$ and $2x$ $\lcm(4x, 2x) = 4x$ $ n = \dfrac{1}{1} \cdot \dfrac{7}{4x} + \dfrac{2}{2} \cdot \dfrac{1}{2x} $ $n = \dfrac{7}{4x} + \dfrac{2}{4x}$ $n = \dfrac{7 +2}{4x}$ $n = \dfrac{9}{4x}$